I went outside this evening to feed the rabbit beagles. We have three adults and two puppies, so dividing the food around so that everyone gets their fair share can take a few minutes. After I had rattled the dry chow into their bowls, I sat down to keep guard. My two horses roam freely about the lot outside my yard, and the sound of chow pinging on the bottom of the bowls is a siren song to them.
They came trotting over, anxious to bully their way to a snack and I shooed them off, then sat on a log to wait for the dogs to finish.
As I looked up, I noticed the monarch butterflies. The sky swirled gray and silver in the waning light, and silhouetted against it were several Monarchs, beating their way home. They crossed against the mountains to the west as they headed south, and while I sat there, I counted ten. Then I got interested in counting how often they flap because they seem to be working awful hard. I didn’t get an exact count of wingbeats per minute, but I can tell you that they were beating at least three times faster than my heart. It’s hard to imagine a critter who, born here, knows somehow when it’s time to flap south and head to Mexico, which is where almost all monarchs end up. How do they know where to go?
I have captured and raised more than one for my science classroom. Born from tiny eggs laid exclusively on milkweed leaves, the tiny larvae eat themselves from the size of a comma to the size of a pencil nub in less than three weeks. If you look at the bottom of the plant where they live, you will find a sizable pile of caterpillar poop—little green pellets that they excrete almost as fast as they eat. Then the green and black striped worms diddle themselves a little pad of silk and hook their back legs in so they can hang head down and transform into a beautiful green and gold chrysalis.
Within two weeks, depending on temperature, the chrysalis becomes translucent and the folded up shape of the future butterfly becomes visible. It only takes the monarch minutes to break free. Then it hangs head down so gravity can move fluid into its flaccid wings. In an hour the butterfly is ready. It pumps its wings and lifts off.
We released a few from my classroom this week and I was amazed to see them immediately orient themselves and then start to flap south. How do they know which way to go? Anyway those were my thoughts as I watched the Halloween striped beauties wing their way home this evening. Wouldn’t it be nice if we could orient ourselves so we could head home with as much boldness as these tiny flapping wonders?
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